GMC Hummer H3 2008 Owner's Handbook Manual page 221

Starting and Operating Instructions
• Surface conditions can be a
problem when you drive across
a hill. Loose gravel, muddy
spots, or even wet grass can
cause your tyres to slip side-
ways, down-hill. If the vehicle
slips sideways, it can hit some-
thing that will trip it (a rock, a
rut, etc.) and it will roll over.
. . . 220
• Hidden obstacles can make the
steepness of the incline even
worse. If you drive across a rock
with the up-hill wheels, or if
the down-hill wheels drop into
a rut or depression, your vehi-
cle can tilt even worse.
For reasons like these, you need to
decide carefully whether to try to
drive across an incline. Just
because the trail goes across the
incline doesn't mean you have to
drive it. The last vehicle to try it
might have rolled over.
CAUTION
Driving across an incline that's
too steep will make your vehicle
roll over. You could be seriously
injured or killed. If you have any
doubt about the steepness of
the incline, don't drive across it.
Find another route instead.
CAUTION
Getting out on the down-hill
(low) side of a vehicle stopped
across an incline is dangerous. If
the vehicle rolls over, you could
be crushed or killed. Always get
out on the up-hill (high) side of
the vehicle and stay well clear of
the roll-over path.